Aren
/
NetBSD
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity
NetBSD/gnu/dist/postfix/html/smtp.8.html

333 lines
11 KiB
HTML
Raw Blame History

<html> <head> </head> <body> <pre>
SMTP(8) SMTP(8)
<b>NAME</b>
smtp - Postfix remote delivery via SMTP
<b>SYNOPSIS</b>
<b>smtp</b> [generic Postfix daemon options]
<b>DESCRIPTION</b>
The SMTP client processes message delivery requests from
the queue manager. Each request specifies a queue file, a
sender address, a domain or host to deliver to, and recip-
ient information. This program expects to be run from the
<a href="master.8.html"><b>master</b>(8)</a> process manager.
The SMTP client updates the queue file and marks recipi-
ents as finished, or it informs the queue manager that
delivery should be tried again at a later time. Delivery
problem reports are sent to the <a href="bounce.8.html"><b>bounce</b>(8)</a> or <a href="defer.8.html"><b>defer</b>(8)</a> dae-
mon as appropriate.
The SMTP client looks up a list of mail exchanger
addresses for the destination host, sorts the list by
preference, and connects to each listed address until it
finds a server that responds.
When the domain or host is specified as a comma/whitespace
separated list, the SMTP client repeats the above process
for all destinations until it finds a server that
responds.
Once the SMTP client has received the server greeting ban-
ner, no error will cause it to proceed to the next address
on the mail exchanger list. Instead, the message is either
bounced, or its delivery is deferred until later.
<b>SECURITY</b>
The SMTP client is moderately security-sensitive. It talks
to SMTP servers and to DNS servers on the network. The
SMTP client can be run chrooted at fixed low privilege.
<b>STANDARDS</b>
<a href="http://www.faqs.org/rfcs/rfc821.html">RFC 821</a> (SMTP protocol)
<a href="http://www.faqs.org/rfcs/rfc1651.html">RFC 1651</a> (SMTP service extensions)
<a href="http://www.faqs.org/rfcs/rfc1870.html">RFC 1870</a> (Message Size Declaration)
<a href="http://www.faqs.org/rfcs/rfc2197.html">RFC 2197</a> (Pipelining)
<a href="http://www.faqs.org/rfcs/rfc2554.html">RFC 2554</a> (AUTH command)
<b>DIAGNOSTICS</b>
Problems and transactions are logged to <b>syslogd</b>(8). Cor-
rupted message files are marked so that the queue manager
can move them to the <b>corrupt</b> queue for further inspection.
Depending on the setting of the <b>notify</b><i>_</i><b>classes</b> parameter,
the postmaster is notified of bounces, protocol problems,
and of other trouble.
1
SMTP(8) SMTP(8)
<b>BUGS</b>
<b>CONFIGURATION</b> <b>PARAMETERS</b>
The following <b>main.cf</b> parameters are especially relevant
to this program. See the Postfix <b>main.cf</b> file for syntax
details and for default values. Use the <b>postfix</b> <b>reload</b>
command after a configuration change.
<b>Miscellaneous</b>
<b>best</b><i>_</i><b>mx</b><i>_</i><b>transport</b>
Name of the delivery transport to use when the
local machine is the most-preferred mail exchanger
(by default, a mailer loop is reported, and the
message is bounced).
<b>debug</b><i>_</i><b>peer</b><i>_</i><b>level</b>
Verbose logging level increment for hosts that
match a pattern in the <b>debug</b><i>_</i><b>peer</b><i>_</i><b>list</b> parameter.
<b>debug</b><i>_</i><b>peer</b><i>_</i><b>list</b>
List of domain or network patterns. When a remote
host matches a pattern, increase the verbose log-
ging level by the amount specified in the
<b>debug</b><i>_</i><b>peer</b><i>_</i><b>level</b> parameter.
<b>disable</b><i>_</i><b>dns</b><i>_</i><b>lookups</b>
Disable DNS lookups. This means that mail must be
forwarded via a smart relay host.
<b>error</b><i>_</i><b>notice</b><i>_</i><b>recipient</b>
Recipient of protocol/policy/resource/software
error notices.
<b>fallback</b><i>_</i><b>relay</b>
Hosts to hand off mail to if a message destination
is not found or if a destination is unreachable.
<b>ignore</b><i>_</i><b>mx</b><i>_</i><b>lookup</b><i>_</i><b>error</b>
When a name server fails to respond to an MX query,
search for an A record instead deferring mail
delivery.
<b>inet</b><i>_</i><b>interfaces</b>
The network interface addresses that this mail sys-
tem receives mail on. When any of those addresses
appears in the list of mail exchangers for a remote
destination, the list is truncated to avoid mail
delivery loops.
<b>notify</b><i>_</i><b>classes</b>
When this parameter includes the <b>protocol</b> class,
send mail to the postmaster with transcripts of
SMTP sessions with protocol errors.
2
SMTP(8) SMTP(8)
<b>smtp</b><i>_</i><b>always</b><i>_</i><b>send</b><i>_</i><b>ehlo</b>
Always send EHLO at the start of a connection.
<b>smtp</b><i>_</i><b>never</b><i>_</i><b>send</b><i>_</i><b>ehlo</b>
Never send EHLO at the start of a connection.
<b>smtp</b><i>_</i><b>skip</b><i>_</i><b>4xx</b><i>_</i><b>greeting</b>
Skip servers that greet us with a 4xx status code.
<b>smtp</b><i>_</i><b>skip</b><i>_</i><b>5xx</b><i>_</i><b>greeting</b>
Skip servers that greet us with a 5xx status code.
<b>smtp</b><i>_</i><b>skip</b><i>_</i><b>quit</b><i>_</i><b>response</b>
Do not wait for the server response after sending
QUIT.
<b>smtp</b><i>_</i><b>bind</b><i>_</i><b>address</b>
Numerical network address to bind to when making a
connection.
<b>Authentication</b> <b>controls</b>
<b>smtp</b><i>_</i><b>enable</b><i>_</i><b>sasl</b><i>_</i><b>auth</b>
Enable per-session authentication as per <a href="http://www.faqs.org/rfcs/rfc2554.html">RFC 2554</a>
(SASL). By default, Postfix is built without SASL
support.
<b>smtp</b><i>_</i><b>sasl</b><i>_</i><b>password</b><i>_</i><b>maps</b>
Lookup tables with per-host or domain <i>name</i>:<i>password</i>
entries. No entry for a host means no attempt to
authenticate.
<b>smtp</b><i>_</i><b>sasl</b><i>_</i><b>security</b><i>_</i><b>options</b>
Zero or more of the following.
<b>noplaintext</b>
Disallow authentication methods that use
plaintext passwords.
<b>noactive</b>
Disallow authentication methods that are
vulnerable to non-dictionary active attacks.
<b>nodictionary</b>
Disallow authentication methods that are
vulnerable to passive dictionary attack.
<b>noanonymous</b>
Disallow anonymous logins.
<b>Resource</b> <b>controls</b>
<b>smtp</b><i>_</i><b>destination</b><i>_</i><b>concurrency</b><i>_</i><b>limit</b>
Limit the number of parallel deliveries to the same
destination. The default limit is taken from the
<b>default</b><i>_</i><b>destination</b><i>_</i><b>concurrency</b><i>_</i><b>limit</b> parameter.
3
SMTP(8) SMTP(8)
<b>smtp</b><i>_</i><b>destination</b><i>_</i><b>recipient</b><i>_</i><b>limit</b>
Limit the number of recipients per message deliv-
ery. The default limit is taken from the
<b>default</b><i>_</i><b>destination</b><i>_</i><b>recipient</b><i>_</i><b>limit</b> parameter.
<b>Timeout</b> <b>controls</b>
The default time unit is seconds; an explicit time unit
can be specified by appending a one-letter suffix to the
value: s (seconds), m (minutes), h (hours), d (days) or w
(weeks).
<b>smtp</b><i>_</i><b>connect</b><i>_</i><b>timeout</b>
Timeout for completing a TCP connection. When no
connection can be made within the deadline, the
SMTP client tries the next address on the mail
exchanger list.
<b>smtp</b><i>_</i><b>helo</b><i>_</i><b>timeout</b>
Timeout for receiving the SMTP greeting banner.
When the server drops the connection without send-
ing a greeting banner, or when it sends no greeting
banner within the deadline, the SMTP client tries
the next address on the mail exchanger list.
<b>smtp</b><i>_</i><b>helo</b><i>_</i><b>timeout</b>
Timeout for sending the <b>HELO</b> command, and for
receiving the server response.
<b>smtp</b><i>_</i><b>mail</b><i>_</i><b>timeout</b>
Timeout for sending the <b>MAIL</b> <b>FROM</b> command, and for
receiving the server response.
<b>smtp</b><i>_</i><b>rcpt</b><i>_</i><b>timeout</b>
Timeout for sending the <b>RCPT</b> <b>TO</b> command, and for
receiving the server response.
<b>smtp</b><i>_</i><b>data</b><i>_</i><b>init</b><i>_</i><b>timeout</b>
Timeout for sending the <b>DATA</b> command, and for
receiving the server response.
<b>smtp</b><i>_</i><b>data</b><i>_</i><b>xfer</b><i>_</i><b>timeout</b>
Timeout for sending the message content.
<b>smtp</b><i>_</i><b>data</b><i>_</i><b>done</b><i>_</i><b>timeout</b>
Timeout for sending the "<b>.</b>" command, and for
receiving the server response. When no response is
received, a warning is logged that the mail may be
delivered multiple times.
<b>smtp</b><i>_</i><b>quit</b><i>_</i><b>timeout</b>
Timeout for sending the <b>QUIT</b> command, and for
receiving the server response.
4
SMTP(8) SMTP(8)
<b>SEE</b> <b>ALSO</b>
<a href="bounce.8.html">bounce(8)</a> non-delivery status reports
<a href="master.8.html">master(8)</a> process manager
<a href="qmgr.8.html">qmgr(8)</a> queue manager
syslogd(8) system logging
<b>LICENSE</b>
The Secure Mailer license must be distributed with this
software.
<b>AUTHOR(S)</b>
Wietse Venema
IBM T.J. Watson Research
P.O. Box 704
Yorktown Heights, NY 10598, USA
5
</pre> </body> </html>
Reference in New Issue View Git Blame Copy Permalink